Treatment patterns and rates of upgrading and upstaging in prostate cancer patients with single GGG1 positive biopsy core.

Abstract

Not infrequently patients are diagnosed with clinically localized prostate based on a single positive biopsy core exhibiting Gleason grade group 1 (GGG1) with variable prostate-specific antigen (PSA) levels. We investigated treatment patterns and hypothesized that regardless of PSA in cT1- to cT2-stage patients, presence of GGG3/GGG4/GGG5 and/or non-organ confined stage will rarely be identified. Within the Surveillance, Epidemiology, and End Results database (2010-2015), clinically localized prostate cancer (CaP) patients with PSA ≤ 50 ng/ml and a single positive GGG1 biopsy core were identified. Overall treatment rates were examined, estimated annual percentage changes and logistic regression analyses were fitted to test for no-local treatment. Subsequently, rates of upgrading (GGG3/GGG4/GGG5) and/or upstaging (≥pT3 and/or pN1) were investigated in radical prostatectomy patients. 13,342 clinically localized CaP patients harbored single GGG1 positive biopsy core at diagnosis. No local treatment was recorded in 5,235 (53.0%) cT1-stage vs. in 1,039 (49.0%) cT2-stage patients. No local treatment rates increased over time from 35.0% to 67.0% vs. 34.0% to 63.0% in cT1 vs. cT2 patients, observations were confirmed in logistic regression analyses (cT1: multivariable odds ratio [mOR]: 1.39; cT2: mOR: 1.33). In radical prostatectomy treated cT1-patients (n = 2,293) and cT2-patients (n = 659), upgrading vs. upstaging vs. upgrading/upstaging combined was 6.1%, 6.5%, 11.0% and 6.2%, 5.0%, 9.9% respectively. In single GGG1 positive biopsy core CaP patients, the combined proportion of upgrading and upstaging should be expected in one tenth. In consequence, the overwhelming majority harbors favorable grade and stage that is compatible with no local treatment.